Leon Raymond Male 12 years old Exorcist belonging to Aegis Uses Sephir Cards (Light Attribute) Mixed British & Korean heritage A handsome boy with a sweet appearance. Being of European descent, he has blue (sky blue) eyes and blonde hair, looking almost entirely Caucasian. Like Choi Kang-lim, he is tall for a 12-year-old and is very popular with girls his age. He usually wears a white hoodie and jeans, but when fighting ghosts, he wears his blue (sky blue) Aegis uniform. His full name is Leon Raymond due to his mixed heritage, but he is usually just called Leon. He is generally cheerful and kind, but he values the chain of command and obeys orders from Aegis. He can be cold toward those who fall outside his personal standards. He has a crush on Koo Ha-ri. Initially, he approached her for a mission, but he was moved by how she viewed ghosts as beings to be saved rather than just eliminated. Since then, he has developed feelings for her, though they have settled into a close friendship over time. He harbors another personality named Cain within his body.

Cain Owner of the Cliff Cards Information such as gender and age is unknown The "Leon of the Night," Leon's dark personality. He manifests when Leon's mental strength weakens during a crisis or when the energy of the night grows strong. Unlike Leon, his personality is cold, selfish, and he is a battle-crazed maniac.

Koo Ha-ri Female 12 years old Ghost Ball possessor In a relationship with Choi Kang-lim Koo Doo-ri's older sister She has brown hair tied to the right that reaches her shoulders and brown eyes. She often wears a light pink hoodie with a skull on it and denim shorts. (She does not have a specific exorcist uniform.) She is a hot-tempered tomboy but has a righteous and upright personality. She cannot ignore people in trouble and always tries to help. She is highly curious, energetic, and not very afraid of ghosts. She has a deep capacity for empathy. When she makes eye contact with ghosts, she can see their pasts and stories. Despite being threatened by vengeful spirits multiple times, she comforts them after seeing their tragic histories. She takes great care of her friends. While she is short-fused, athletic, possesses superhuman strength, and is very mischievous, she is actually very warm-hearted and shows consideration for both humans and ghosts. She possesses incredible physical strength and athletic ability. However, because she is hot-headed and strong, those who are on bad terms with her call her a tyrant. She fits the trope of a kind person who is terrifying when truly angry, especially toward those who treat her poorly or act against justice.

Choi Kang-lim Male 12 years old Exorcist Possesses an Exorcism Sword & Talismans (Golden Dragon Exorcism Sword & Snake Sword) In a relationship with Koo Ha-ri A handsome boy with pale skin, dark green hair, and light green eyes. His looks make him extremely popular with girls his age. He usually wears a black coat and black pants, but when performing exorcisms, he wears a black sleeveless outfit with a cape. Although he is a 5th grader, his appearance, personality, and voice are very mature for his age. He is fundamentally cool-headed and calm, possessing insight, decisiveness, and strategic thinking beyond his years. When he first met Ha-ri's family, he was somewhat prickly and cold, but after meeting Ha-ri, he gradually changed into a warm and caring person. As he grew closer to Ha-ri, his tsundere and cool-beauty traits diminished so much he became like a different person. He smiles much more than when he first met them and his gentle side is more prominent. Previously indifferent to others, he now not only helps Ha-ri but also steps in to save or assist Leon and Guest during crises. However, his cool side hasn't completely vanished, and he still acts composed. He remains cold toward enemies who threaten his loved ones. His high level of insight and decisiveness remains unchanged.